Apparatus for making an offset laminated roofing shingle

ABSTRACT

This invention provides a process and apparatus which automatically and in a continuous and uninterrupted manner laminates a narrow strip of bituminous coated glass mat to the bottom side of a coated glass mat, cuts the laminated product to produce a laminate having cut-out areas between remaining tabs and then adheres thin strips of coated glass mat across the tabs to underlie the tabs and the cut-out areas. The final shingle is made from a single glass mat which is processed into a three level shingle, each level being made of a portion of the original glass mat.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention pertains to the field of roofing shingles.

2. Description of the Prior Art

Roofing shingles have been made in a continuous process in which theapparatus unrolled a felted sheet and immersed the sheet into a bath ofbituminous material to saturate the sheet. The saturated sheet then wascoated with a bituminous coating adhesive spread over its top and bottomsurfaces. Slate roofing granules were applied to its top surface and afine powder or sand was applied to the bottom surface. The shingle wasthen cut into a conventional size of 12 inches by 36 inches forpackaging.

A more recent development which is thought to enhance the appearance ofthe finished shingle roof comprises a two-layer shingle in which anarrow strip of asphalt saturated felt is adhered along the exposed edgeof the shingle to give the roof an improved appearance by presenting tothe viewer's eye a thicker edge for the shingle. However, the laminatingwas accomplished by cutting shingles of two different widths atdifferent times on the roofing machine and then in a hand operationlaminating the narrower strip to the underside of the wider orconventional size shingle. The extra operation has proved to becumbersome and the additional conveying and handling apparatus costlyand space consuming. The extra laminating operation also presentedproblems in exactly aligning the two exposed edges of the laminates andachieving good adhesion.

Current technology comprises a roofing shingle which has a broad centralarea and a narrow strip adhered thereto along one edge of the centralarea. This roofing shingle has cut-out areas along the edge of thecentral strip and in the adhered narrow strip. The process for makingthis improved shingle is described and claimed in U.S. Pat. No.3,998,685, entitled: APPARATUS AND PROCESS FOR MAKING AN OFFSETLAMINATED ROOFING SHINGLE AND ROOFING SHINGLE MADE THEREBY and assignedto The Celotex Corporation.

Recently, the organic felted material of which the roofing shingle usedto be made has been changed to a glass fiber mat which is fireretardant. It is no longer necessary to saturate the glass mat in a bathof asphalt or bitumen. The glass mat is merely coated with an asphaltlayer which also easily penetrates into the mat itself.

A newer development is a shingle which has a broad central area and anarrow strip adhered along one edge of the central area. The combinationshingle has tabs between cut out areas along the edge which has thedouble layer of a wide central area and narrow strip as described in thecited patent. A third layer which is a narrow strip of the same materialis adhered to the tabs to form a layer underlying and bridging the gapswhich separate the tabs.

SUMMARY OF THE INVENTION

This invention provides a process and apparatus which automatically andin a continuous and uninterrupted manner laminates a narrow strip ofbituminous coated glass mat to the bottom side of a coated glass mat,cuts the laminated product to produce a laminate having cut-out areasbetween remaining tabs and then adheres thin strips of coated glass matacross the tabs to underlie the tabs and the cut-out areas. The finalshingle is made from a single glass mat which is processed into a threelevel shingle, each level being made of a portion of the original glassmat. This three-level roofing shingle made by the process is believed tobe more aesthetically attractive than previous roofing shingles.

It is an object of the present invention to provide a novel apparatusfor making a laminated roofing shingle in a continuous operation.

It is a further object of the invention to provide a novel apparatuswhich produces a laminated roofing shingle with a minimum of hand labor.

It is still another object of the present invention to provide a novelroof shingle.

It is yet another object of the invention to provide a novel process formaking a novel laminated roofing shingle in a continuous manner.

Other features and objects of the present invention will become apparentto those skilled in the art when the present description is consideredin the light of the accompanying drawings in which like numeralsindicate like elements and in which:

FIG. 1 is a flow diagram useful in explaining the novel process ofmanufacturing the novel roofing shingle of the invention;

FIGS. 2, 2a, 2b, and 2c are simplified elevational views of the novelapparatus of the invention;

FIG. 3 is a perspective view of the top and bottom sheets laminatedtogether after passing through a slitter;

FIG. 4 is a perspective view of the top and bottom sheets laminatedtogether after passing through a cutter press.

FIG. 5 is a top view of one of the separated sheets after cutting andpassing through a separator; and

FIG. 6 is a perspective view of the novel roofing shingle of theinvention after the third narrow strip is adhered to and below the tabsof the sheet of FIG. 5.

Referring now to the drawings and more specifically to FIG. 1 thereof,there is shown a flow diagram of the novel process of laminating andcutting the laminated sheet to produce a novel roofing shingle. It willbe recognized that many of the basic steps of manufacture of the shingleare conventional and are carried out by well-known standard apparatus tobe found in any roofing plant. The invention resides in the novelprocess, the arrangement of the elements of the apparatus and in thefinal product, the roofing shingle per se.

Hence, in order to avoid undue complexity and to describe the inventionin as concise and complete a fashion as possible, the individual piecesof apparatus such as conventional electric motors, bearings, shafts,rolls, conveyors, frames, nuts, bolts, etc., have not been described.

The process may be described by observing the flow sheet of FIG. 1 andfollowing the arrow which represents the sheet in its initial conditionas a glass fiber mat in the form of a roll and as it continues to thefinished shingle.

The initial sheet is most generally a mat of suitable glass fibers ofapproximately 16 pounds per 1,000 square feet. For purposes of thisinvention, the sheet will preferably be 411/2 inches in width, ormultiples thereof, although other widths can be chosen without departingfrom the scope of the invention. The sheet, as supplied by themanufacturer, is wound on a mandrel or core which is suspended on abracket to permit unwinding of the sheet. The sheet unwind station isindicated by the numeral 10.

The sheet is then fed to a slitter 12 which can be a conventionalbevelled cutting wheel with an anvil roll on the opposite of the sheet.For purposes of the invention, the original 411/2 inch sheet is cut toform two sheets; one 34 inches wide and the other 71/2 inches wide.

The wider of the two sheets is fed to a top coat station 14 where anasphalt top coat is applied to the sheet. At the next station 16, theunderside of the wider sheet passes over a back coater which applies acoat of hot asphalt to it.

Standard granules are dropped on the upper asphalt coating of the uppersheet at the slate applicator station 18. It should be understood thatthe formation of an asphalt coated sheet with top and bottom coatingsand a layer of granules embedded in the top coat is accomplished in aconventional way well-known to those skilled in the art using well-knownmachinery.

The narrower sheet is concurrently moving through a back coating step 20where the underside of the narrower (71/2 inches) sheet is coated withan asphalt coating. Following this coating, the narrower strip isshifted over at station 22 so that the centerline of the narrower stripis coincident with the centerline of the wider strip and the narrowerstrip is under the wider strip.

It will be recalled that the underside of the wider sheet has an asphaltcoating thereon. At station 26, the two sheets are brought into contactwith the centerline of the narrower sheet being coincident with thecenterline of the wider sheet and the narrower sheet being under thewider sheet. The wider sheet has a coating of granules on its uppersurface.

The now laminated sheet continues through a cooling zone 28, and aslitter 30. The slitter is arranged so that it cuts one strip from eachof the outer portions of the newly laminated sheet. The strips are of61/4 inches wide. This leaves a central portion 211/2 inches wide with acenter laminate 71/2 inches along the central axis of the laminatedsheet.

Following this slitting step, a cutting apparatus 31 cuts the laminatedsheet into two separate sheets with the double layer along its centerline. The cut, laminated sheet is separated into two separate sheets bya separator 32. Each of the sheets has tabs separated by cut-outportions and the leading exposed edge of each sheet has a doublethickness; one thickness being the central wider sheet and the otherthickness being the narrower sheet, underlying the wider sheet.

An adhesive applicator 33 applies an adhesive to the exposed undersideof the tabs on each of the separated sheets.

A shim shifter 34 aligns the narrow strips which were cut off thecentral sheet at slitter 30 with the edges of the tabs on the separatedlaminated sheet from separator 32.

A laminator 35 applies the narrow strip from the shim shifter 34 to theunderside of the tabs on the central laminated sheet so that the stripsare adhered to the underside of the tabs to form a three-tiered sheet.The narrow strips cover the cut-out portions between the tabs.

A length cutter 36 cuts the three-tiered sheet into suitable lengths forshingles and a packaging unit 37 accumulates the sheets to form apackage which then is wrapped to form a bundle of shingles.

Suitable standard packaging apparatus 37 may be used to collect, packageand wrap the finished roofing shingle for storage.

Having described the process with the flow diagram, reference may now bemade to FIGS. 2, 2a, 2b, and 2c for a more detailed description of theapparatus. For purposes of simplifying the description, the apparatusfor handling, unwinding the sheet and coating the sheet, will not bedescribed since these are conventional and well-known pieces ofequipment. Also the parts of the apparatus shown in block diagram formin FIG. 1 will be designated generally by the same numerals in FIGS. 2,2a, 2b, and 2c.

Starting at the right-hand edge of FIG. 2, glass mat 40 is pulled byroll 44 and 45 from the sheet unwind unit 10 (not shown on thisdrawing). A slitter 48, which may be a bevelled blade driven on a shaftby a suitable motor (not shown), cuts glass fiber sheet 40 into twoportions, a wide sheet 40a and a narrow sheet 40b. As previouslydiscussed, sheet 40 was preferably 411/2 inches wide while sheet 40a is34 inches wide and sheet 40b is 71/2 inches wide. Obviously thesedimensions are not critical but have been selected for the purpose ofdesigning an attractive, finished product.

Sheets 40a and 40b form loops 41a and 41b respectively by means of pullrollers and guide rollers 50-56. Pull rollers and guide rollers 50-56are conventional means for pulling and guiding sheets of coated glassmat through a roofing machine.

Referring now to FIG. 2a, sheet 40a is conveyed across the upper surfaceof a table 60 and between rolls 62 and 63. Roll 62 applies a coat of hotasphalt over the upper surface of sheet 40a from a pool of hot asphalt65 maintained in a tank 67. Heaters 68 keep the coating asphalt at theproper temperature for application. Back up roll 63 keeps sheet 40a incontact with application roll 62 during the coating operation. Sheet 40aproceeds past back coating roller 70 which, with a doctor roll 72 tocontrol thickness, applies a coating of hot liquid asphalt 65 to theback or under surface of sheet 40a. A doctor blade 74 removes excesscoating from the back or under surface of sheet 40a. Guide and drivingrolls 75 and 76 pull sheet 40a along.

Referring now to FIG. 2b, roofing granules are dropped on the uppersurface of sheet 40a at granule or slate applicator 18 where they becomeembedded in the top asphalt coat. The application of the granules isindicated by the arrows 80. The granules are fed from a granule hopper(not shown) and applied in a conventional manner. Sheet 40a continuesover guide roll 82 to the outer surface of a laminating roll 85 atstation 26. Laminating roll 85 also serves to press the granules firmlyinto the top coating of asphalt on the upper surface of sheet 40a.

Reverting now to sheet 40b and to FIG. 2a, sheet 40b is moved below tank67 and across guide rolls 90, 91 and 92.

At station 20 a tank 95 holds hot liquid asphalt 98 and a roll coater 99is partially immersed in asphalt 98 and contacts the under surface ofshim sheet 40b to apply an undercoating thereto. Suitable doctor blades100, 101 and 102 adjust the thickness of the coating on shim sheet 40b.

Sheet 40b proceeds to station 22 where it is shifted over so that itscenterline is coincident with the centerline of sheet 40a. It is notnecessary that the location of the shifting apparatus for repositioningshim sheet 40b be located after the coating operation, but it issufficient that this shift take place between cutter 48 and laminatingroll 85.

It will be recalled that sheet 40a runs over the outer periphery oflaminating roll 85 at station 26. As can be seen now, sheet 40b, whichis 71/2 inches wide, lies against the underside of sheet 40a, which is34 inches wide. The centerlines of the sheets are coincident. Theasphalt coating applied to the under surface of sheet 40a serves as anadhesive to form a laminated sheet 110.

Sheet 110 passes through a cooling section 28 which may be cooling drumsor simply a water spray system 105 which lowers the temperature of thelaminated sheet 110 to set the adhesive action of the coating betweensheet 40a and shim sheet 40b.

Laminated sheet 110 enters slitter 30 which comprises a pair of uppercutter blades 120 and lower backer rolls 121 (only one set of each pairis shown). Each set of the pair of cutter blades 120 and backer rolls121 is spaced from the other set by a distance of 211/2 inches. Thus,when sheet 110 passes through slitter 30, there are three stripsemerging from the slitter. The center strip which comprises thelaminated central area 126 is 211/2 inches in width while the two outerstrips 125 and 127 are each 61/4 inches in width.

Reference may be had to FIG. 3 which shows the sheet as it emerges fromslitter 30.

The central laminated sheet 126 continues on to a cutter 31 comprisingan upper cutter drum 128 and a back-up drum 129 which cuts sheet 126into two separable strips 135 and 136. The outer surface of drum 128 hasa preset pattern so that the two strips emerging therefrom have repeatedinterdigitating tabs 130 and 131 as shown in FIG. 4. As can be seen inFIG. 4, there are two separable elongated strips with an underlyingnarrower strip adhered to a wider overlying strip.

After laminated strip 126 is cut into two strips 135 and 136, they areseparated at station 32. Station 32 may be two drums 138 and 139 whichare positioned to rotate at an angle with respect to each other so thatthe two strips 135 and 136 will go on separate paths along conveyorbelts (not shown).

In FIG. 2c to the right of the separator 32, there is shown a top viewof the separated strips illustrating the tabs 130 and 131 and theintermediate cut-outs 144 and 145 which are better shown in FIG. 5.

Each strip 135 and 136 continues on to an adhesive applicator 33. Theupper adhesive applicator 33 comprises an applicator drum 150 and atrough 151 in which applicator drum 150 is partially immersed. Laminatedstrip 135 rides over the upper surface of drum 150 which applies anadhesive from trough 151 to the underside of tabs 131 of the strip 135.In the same way a lower applicator (represented by numerals 150' and151') applies adhesive to the underside of tabs 130 of strip 136.

Strips 125 and 127 which were cut from the laminated sheet 110 atslitter 30 are conveyed over conveyors 155 and 156 and shifted at shimshifter 34 so that they become aligned with the outer edges of tabs 131and 130, respectively. Strips 125 and 127 underlie the tabs 131 and 130and also the cut-out portions 144 and 145. Shim shifter 34 may compriseoffset rolls 157 and 158 which rotate around axes at an angle withrespect to conveyors 155 and 156 respectively.

At station 35, the strips 125 and 127 are laminated to tabs 131 and 130respectively by laminating drums 160 and 161. The drums 160 and 161provide surfaces against which the strips 125 and 127 are held againsttabs 131 and 130 of strips 135 and 136 respectively.

The three-tiered strips 165 and 166 are conveyed to a cutting station 36which comprises cutting drums 170 and 171 each with its back-up roll 173and 174 repectively. Cutting drums 170 and 171 have sharp projectingstrips spaced around their peripheries at preset intervals to cut strips165 and 166 into separate roofing shingles.

Roofing shingles 175 and 176 are conveyed to a packaging station 37which is a conventional shingle packing station.

FIG. 6 illustrates the novel roofing shingle of the invention by showingit in perspective. The main sheet 175 has a straight single layer upperedge 180 and a triple level lower edge. The lower edge 181 has an upperlayer comprising the main sheet 135 with an intermediate layercomprising the laminated sheet 40b and a bottom layer comprising thecontinuous strip 125. The cut-out portions 144 are shown to be only twolayers in depth with the bottom layer 125 covering the cut-out portions.The tabs 131 are three layers thick because of the addition of strip 125to their underside.

The width of the strip 125 is wider than the length of a tab 131 andequal to the width of intermediate sheet 40b so that strip 125 underliestabs 131 and also the underside of the central laminate sheet 40b.

Certain changes can be made in the process, if desired. For example, itwould be possible to perform the slitting operation which forms sheets40a and 40b out of sheet 40 at a location other than that shown. Sheet40 could be left intact until after it has been top coated and thegranules applied. Then, after slitting, sheets 40a and 40b could belaminated leaving a layer of granules between the two sheets. Thisprocess would produce a thicker butt shingle without adding appreciablyto the complexity of the process.

In order to show that much of the general machinery and process is wellknown to those skilled in the art, it is intended to incorporate in thisdisclosure the following publication:

"Manufacture, Selection and Application of Asphalt Roofing and SidingProducts" by N. L. Strahan and published by Asphalt RoofingManufacturers Association of 757 Third Avenue, New York, N.Y. 10017,copyrighted, 1966.

In summary there has been disclosed an apparatus, and process for makinga novel roofing shingle by cutting a single web into two parts,laminating the two parts with coincident centerlines, and then cutting apair of strips from along edge portions of the laminated sheet, cuttingthe laminated sheet into two strips with interdigitating tabs,separating the two strips and laminating the pair of strips to the tabsof the laminated sheets to form a tri-level thick butt shingle from asingle sheet of material. The novel apparatus and the novel roofingshingle are described.

While the present invention has been described with respect to specificembodiments thereof, it should be understood that the invention is notlimited thereto as many modifications thereof can be made. It is,therefore, contemplated to cover by the present application any and allsuch modifications as fall within the spirit and scope of the appendedclaims.

We claim:
 1. An apparatus for making a roofing shingle from a glass matcomprising means for longitudinally slitting said glass mat into twosheets each having a respective centerline and two sides, means forlaterally shifting one of said last mentioned sheets so that therespective centerlines are coincident, means for applying an adhesive toone side of one of said latter mentioned sheets, means for laminatingsaid latter mentioned sheets in overlapping relation to form a laminatedsheet, means for cutting narrow strips from opposite edges of saidlaminated sheet, cutting means for severing said laminated sheet intoindividual strips, said individual strips having alternating tabs andcut-out portions, means for separating said individual strips, means foradhering said narrow strips to said tabs along one edge of each of saidindividual strips and cutting means for cutting said individual stripsinto preselected lengths, whereby a tri-level laminated roofing shingleis made.
 2. An apparatus for making a roofing shingle as recited inclaim 1 in which said slitting means is offset from the longitudinalcenterline of said saturated glass mat whereby said latter mentionedsheets are of different widths.
 3. An apparatus for making a roofingshingle as recited in claim 1 in which said apparatus has means forapplying roofing granules to the top surfaces of one of said lastmentioned sheets.